Connecting rod orientation

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ajparry89

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Doing a rebuild on a 5.7 out of a 2010. Not my first rebuild, nor my first hemi. Along the way, had some miscommunication with my buddy who was helping me, and the piston/rods got mixed up.
We grinder down the carbon and found all the arrows on the pistons, then marked which way they were positioned on the rods, and put the new pistons on the rods the same way they were. It seemed that the difference was, on the rods, here is a slight slight wider shoulder (if that’s what you call it) on one side around the rod bearing. And when keeping all the piston arrows pointing forward, 4 rods have the wider shoulder toward the front, and 4 have it toward the rear - that seems to be the difference between the left and right. Am I right so far?

so I measured the offset, looking down the cylinder, which way the cylinder was slightly off center of the crank journal, and got them correct or what seemed correct. Everything went together great, no issues, spin so nice and freely, I could spin it by hand with all pistons in (no compression) no binding or nothing.
Got it all together, and after about 10-15 seconds of cranking, it locked up. Tore the pan off and the wrist pins are seized in the pistons! Like 3 or 4 of them. Some on each side. But no pattern. Never seen anything like this! Another engine builder looked at it and can’t figure it out either.
Anybody have any idea what could have gone wrong? I’m open to the idea that my rods are on the wrong side? But it just doesn’t seem that way. If switched them, the offset would be too great I think and would bind even tryin to turn by hand.
Anybody have a way of knowing for sure which way the rods are supposed to face?
You don’t have to reply saying I need to mark them. I know that, like I said, a miscommunication. I’ve done hemis before. Looking for some help here, I’m tearing it all back apart now, but want to do it right this time lol. Thanks!
 
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ajparry89

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Bump! Anybody have any idea of a place/shop I could call who would know? There has to be a way to determine for sure which way the rods face, other than the arrow on the piston. when the rods are made at the factory, the pistons are not on them yet lol. any suggestions, let me know, thank you!
 

dhay13

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yes. I have never built a Chrysler engine but all others I have done the chamfer does face the crank counterweight. This is because the edge of the machine surface is beveled but in my experience if you get these wrong you can't even turn it by hand so not certain that is your problem.

BTW-I always stamped my rods to be sure they went back into the same hole but if you have the rods re-sized that isn't as important.
 
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ajparry89

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yes the chamfer did always face the counter weight. two rods per each of the 4 journals on the crank...and one chamfer faced the forward counter weight and one faced the rear. in other words, the two chamfers on each rod faced away from eachother.

and yes, for all those reading, they need to be marked and put back in the same place to be safe!!
stupid miscommunication on our end, i have had a buddy helping me with this one.

So I am glad to hear that I probably did not do anything wrong. but I am frustrated to hear that I still do not know what to do differently!! lolol.

side note: Thanks for teaching me a new word...chamfer!
 

Wild one

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